This project investigates the neural and cognitive executive processes mediated by the human prefrontal cortex (PFC) that monitor and control human behavior. Specifically, the role of attention, selection, inhibition, working memory and other executive control processes required to perform perceptual-motor tasks like those involved in driving an automobile or piloting an airplane. This project will focus on how these processes change with practice and vary across individuals of different skill levels. These experiments will investigate executive control using functional magnetic resonance imaging (fMRI). Experiments 1 and 2 will identify the brain regions associated with the cognitive processes responsible for selecting appropriate responses to presented stimuli, both early in learning a task and after it has been well practiced. Experiments 3 and 4 will pair two perceptual motor tasks in a dual-task procedure to investigate the executive control processes required to successfully perform multiple tasks simultaneously. These experiments will differ in the level of difficulty of the two tasks and will identify behaviorally "good" and "bad" dual-task performers. The neuroimaging and behavioral results will be used in conjunction to identify how cognitive executive processing differs in task performers at various levels of skill acquisition. Executive control processes play a major role in many theories of human information processing. Thus, understanding the neural and cognitive nature of these processes in human performance is theoretically important and will advance our understanding of the human information processing system in many cognitive domains.